Horrible non-ending explanations that NOBODY AT VODACOM SEEMS TO UNDERSTAND

I took out a 2nd contract end March 2017. They delivered 2 phones instead of 1. I sent one back. We then realise the one that we kept was on another package than what we requested. Since then I contacted Vodacom and "migrated" to the right package pay as you go with "top-up" as the phone is for my daughter. They migrate me and ask to pay for migration. Then, I realise once again, they migrated to the wrong package again and so it has been going on since April 2017. I think I was migrated 5 x times already!!!! They gave my daughter an OPEN LINE EVERY TIME! I AM NOT GOING TO PAY THAT AMOUNT. I WAS CREDITED FOR ONE MONTH, BUT REFUSE TO PAY ALL THE OTHER MONTHS FOR YOUR MISTAKE. It now shows of course that I am in arrears, but I will not pay for something I did not ask. I CAN NOT CANCEL THE CONTRACT, I CAN NOT GO OVER TO ANOTHER SERVICE PROVIDER, I CANNOT CHANGE TO PAY AS YOU GO TO KEEP THE NUMBER BECAUSE OF YOUR MISTAKE. I have been with Vodacom for ages, but I am fed up to try and explain the whole thing over and over and over and over sine April. FIX THIS PROBLEM!!!!